/* ---------------------------------------------------------------------------------------
 * 
 * snapbuild.h
 *	  Exports from replication/logical/snapbuild.c.
 *
 * Copyright (c) 2012-2014, PostgreSQL Global Development Group
 * 
 * 
 * IDENTIFICATION
 *        src/include/replication/snapbuild.h
 *
 * ---------------------------------------------------------------------------------------
 */
#ifndef SNAPBUILD_H
#define SNAPBUILD_H

#include "access/xlogdefs.h"
#include "utils/snapmgr.h"

typedef enum {
    /*
     * Initial state, we can't do much yet.
     */
    SNAPBUILD_START = -1,
    /*
     * Collecting committed transactions, to build the initial catalog
     * snapshot.
     */
    SNAPBUILD_BUILDING_SNAPSHOT = 0,

    /*
     * We have collected enough information to decode tuples in transactions
     * that started after this.
     *
     * yet, because they might be based on transactions that were still running
     * when FULL_SNAPSHOT was reached.
     */
    SNAPBUILD_FULL_SNAPSHOT = 1,

    /*
     * Found a point after SNAPBUILD_FULL_SNAPSHOT where all transactions that
     * were running at that point finished. Till we reach that we hold off
     * calling any commit callbacks.
     */
    SNAPBUILD_CONSISTENT = 2
} SnapBuildState;

/* forward declare so we don't have to expose the struct to the public */
struct SnapBuild;
typedef struct SnapBuild SnapBuild;

/* forward declare so we don't have to include reorderbuffer.h */
struct ReorderBuffer;
struct ParallelReorderBuffer;

/* forward declare so we don't have to include heapam_xlog.h */
struct xl_heap_new_cid;
struct xl_running_xacts;

extern void CheckPointSnapBuild(void);

extern SnapBuild* AllocateSnapshotBuilder(
    struct ReorderBuffer* cache, TransactionId xmin_horizon, XLogRecPtr start_lsn, bool need_full_snapshot);
extern void FreeSnapshotBuilder(SnapBuild* cache);

extern void SnapBuildSnapDecRefcount(Snapshot snap);

extern Snapshot SnapBuildInitialSnapshot(SnapBuild *builder);
extern const char* SnapBuildExportSnapshot(SnapBuild* snapstate);
extern void SnapBuildClearExportedSnapshot(void);

extern SnapBuildState SnapBuildCurrentState(SnapBuild* snapstate);

extern bool SnapBuildXactNeedsSkip(SnapBuild* snapstate, XLogRecPtr ptr);

extern void SnapBuildCommitTxn(
    LogicalDecodingContext *ctx, XLogRecPtr lsn, TransactionId xid, int nsubxacts, TransactionId* subxacts);
extern bool SnapBuildProcessChange(SnapBuild* builder, TransactionId xid, XLogRecPtr lsn);
extern void SnapBuildProcessNewCid(LogicalDecodingContext *ctx, TransactionId xid, XLogRecPtr lsn, struct xl_heap_new_cid* cid,
                                   int bucket_id);
extern void SnapBuildProcessRunningXacts(SnapBuild* builder, XLogRecPtr lsn, struct xl_running_xacts* running);
extern void SnapBuildSerializationPoint(SnapBuild* builder, XLogRecPtr lsn);

extern void SnapBuildSetInitXmin(SnapBuild* builder, TransactionId xmin);
extern void SnapBuildSetState(SnapBuild* builder, SnapBuildState s_state);
#endif /* SNAPBUILD_H */
